sgiaction_sample.c

Linux网络编程PPT和源码,供学习参考

#include <signal.h>
#include <unistd.h>
#include <sys/types.h>
	
void sig_handle(int signum,siginfo_t *sig_info,void *other)
{
	//用于防止同时发送多个信号(采用阻塞的方法)
	sigset_t siglist;
	sigemptyset(&siglist);	//初始化信号集 siglist
	sigaddset(&siglist,SIGUSR2);	//将SIGUSR2加入信号集siglist
	sigprocmask(SIG_BLOCK,&siglist,NULL);	//改变当前的阻塞信号为siglist
	int i;
	printf("start...\n");
	for(i=0;i<5;i++)
	{
		printf("ding....\n");
		sleep(1);
	}
	printf("end...\n");
	printf("signal value %d\n",sig_info->si_int);
	//printf("send process id %d\n",sig_info->si_pid);
}

int main(int argc,char *argv[])
{
	pid_t child;	
	child=fork();	//创建子进程
	if(child==0)
	{
		struct sigaction sigct;
		sigct.sa_sigaction=sig_handle;	//关联信号处理函数
		sigct.sa_flags=SA_SIGINFO;
		sigaction(SIGUSR2,&sigct,NULL);	//安装用户自定义信号
		while(1)
		{
			//printf("ssss\n");
			sleep(1);	
		}
		exit(0);	
	}
	sleep(2);
	union  sigval sig_val;
	sig_val.sival_int=200;	//设定信号携带的数据值
	printf("parent id %d\n",getpid());
	sigqueue(child,SIGUSR2,sig_val);	//给子进程发送SIGUSR2信号,并携带sig_val
	return 0;
}